Signs It's Time to Replace a Flat Roof (and When a Restoration Will Do)
By High Country Roofing · Family-owned commercial roofers in Emmett, Idaho
Most owners don't replace a flat roof until a leak lands on inventory or equipment. By then the repair bill is usually bigger than it had to be. Here's what to watch for, and how to tell a roof that needs replacing from one that can be restored.
The warning signs
- Cracked, blistered or alligatored surface. When the membrane or coating is cracked across the whole roof rather than in a few spots, it has reached the end of its life.
- Open or lifting seams. Idaho's hot summers and freeze-thaw winters work seams loose. A few can be repaired; seams failing everywhere are a replacement sign.
- Water standing 48 hours after rain or snowmelt. Ponding speeds up wear and adds weight. If it keeps coming back, the cause may be slope, drainage or a sagging deck.
- Soft spots underfoot. A spongy roof usually means wet insulation or a damaged deck underneath.
- Leaks in more than one area, or leaks that come back after they've been patched.
- Ceiling stains, musty smells or mold, which mean water has been getting in for a while.
Replace or restore?
Not every old roof needs to come off. If the roof is still dry and solid underneath, a coating restoration can seal the seams and add years of life for much less than a tear-off, with no tear-off mess and your business open. We restored about 100,000 sq ft of metal roof at the Ford Idaho Sports Center in Nampa that way.
If the insulation is wet or the deck is damaged, a coating would just trap the problem. That roof needs replacing, and we install heat-welded Duro-Last PVC or TPO. Compare the two options side by side.
How to know for sure
An inspection tells you which side of the line your roof is on. We walk the roof, photograph every problem, and when it's needed we moisture-test or take a core sample to see what's under the surface. You get a photo report with repairs ranked by priority. Book a free roof inspection.
Common questions
How long does a flat roof last?
It depends on the system, how it was installed and how it's been maintained. A yearly inspection and prompt repairs are the biggest factors you control.
Can you put a new roof over the old one?
Sometimes. A coating restoration goes over a sound existing roof. A new membrane can sometimes go over an old one, but wet insulation has to come out first. Your inspection will tell you.